/******************************************************************************
 * This program is a 100% Java Email Server.
 ******************************************************************************
 * Copyright (c) 2001-2011, Eric Daugherty (http://www.ericdaugherty.com)
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *   * Neither the name of the copyright holder nor the
 *     names of its contributors may be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER ''AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 ******************************************************************************
 * For current versions and more information, please visit:
 * http://javaemailserver.sf.net/
 *
 * or contact the authors at:
 * java@ericdaugherty.com
 * andreaskyrmegalos@hotmail.com
 *
 ******************************************************************************
 * This program is based on the CSRMail project written by Calvin Smith.
 * http://crsemail.sourceforge.net/
 ******************************************************************************
 *
 * $Rev$
 * $Date$
 *
 ******************************************************************************/

package com.ericdaugherty.mail.server.auth;

//Java Imports
import java.io.UnsupportedEncodingException;
import javax.security.sasl.SaslException;

//Encoding Imports
import org.apache.commons.codec.binary.Base64;

//Local Imports
import com.ericdaugherty.mail.server.errors.MalformedBase64ContentException;

/**
 * Verify client authentication using LOGIN.
 *
 * @author Andreas Kyrmegalos
 */
public class LoginServerMode extends PlainServerMode{

   private String username;

   public LoginServerMode(boolean isSMTP) {
      super(isSMTP);
   }

   @Override
   public byte[] evaluateResponse(byte[] responseBytes) throws SaslException{
      if (!Base64.isArrayByteBase64(responseBytes)) {
         throw new SaslException("Can not decode Base64 Content",new MalformedBase64ContentException());
      }
      if (username==null) {
         try {
            username = new String(Base64.decodeBase64(responseBytes), "UTF-8");
            return new byte[0];
         }
         catch (UnsupportedEncodingException uee) {
            throw new SaslException(uee.getMessage());
         }
      }
      else {
         try {
            return finalizeAuthentication.finalize(username, new String(Base64.decodeBase64(responseBytes), "UTF-8"));
         }
         catch (UnsupportedEncodingException uee) {
            throw new SaslException(uee.getMessage());
         }

      }
   }

   @Override
   public void conclude() {
      super.conclude();
      username = null;
   }

}
